Pioneer 2 / PeopleBot - Manual (Page 48)

Pioneer 2 Operating System
number of bytes you request via the GETAUX command—up to 200 bytes at a time.
P2OS waits to collect the requested number of incoming AUX-port serial bytes before
sending the GETAUX packet to the client. Use the GETAUX command with a zero
argument to flush the P2OS circular buffer and reset its pointers.
In the code example above, a fictitious command gets sent to a serial device attached
to the microcontroller's AUX port and retrieves a 10-byte response from that device (note
that ellipses mark the many portions of a complete client that have been deleted for
brevity).
ENCODERpac and ENCODER Command
Issue the ENCODER command #19 with an argument of 1 for a single or with an argument
of 2 or more for a continuous stream of ENCODERpac (type 144; 0x90) SIPs. Discontinue
the packets by sending the ENCODER command #19 with the argument 0.
Table 8. P2OS Encoder Server Information Packet Contents
Header integer Exactly 0xFA, 0xFB
Byte Count byte Number of data bytes + 2 (checksum)
Left Encoder integer Least significant, most significant portion of the
integer current 4-byte raw encoder count from the left drive wheel
Right Encoder integer Least significant, most significant portion of the
integer current 4-byte raw encoder count from the left drive wheel
Checksum integer Checksum for packet integrity
GRIPPERpac and GRIPREQUEST
To ameliorate a few shortcoming when we transferred connection and control of the P2
Gripper accessory from User I/O to the General I/O bus, P2OS 1.E introduced and we
improved the new GRIPPERpac (type=224; 0xE0) packet type and related GRIPREQUEST
P2OS command #37 in P2OS 1_F.
Table 9. Gripper packet contents (P2OS 1_F and later)
Header integer Exactly 0xFA, 0xFB
Byte Count byte Number of data bytes + 2 (checksum)
Type byte Packet type = 0xE0
HasGripper byte Gripper type: 0=none; 1=User; 2=General I/O
Grip_state byte See Table 12 and P2 Gripper Manual
Grasp_Time byte See P2 Gripper Manual
Checksum integer Computed checksum
Normally disabled, your client program must request one (command argument 1) or a
continuous stream (command argument > 1) of Gripper packets. Send GRIPREQUEST
with the argument value 0 to stop continuous packets.
PLAYLISTpac and PLAYLIST Command
Unlike its Pioneer and PeopleBot cousins, the AmigoBot mobile robot has onboard sound
reproduction hardware and software that includes a playlist of contents. To support the
ActivMedia Robotics Basic Suite that includes all ActivMedia’s robots, we’ve added the
PLAYLISTpac
(type = 208; 0xD0) and PLAYLIST request command #91 to P2OS 1.E. We
document the command and packet here for completeness, but they have no effect
on the operation or performance of your Pioneer 2 or PeopleBot Mobile Robot.
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